Let's take getting a new muffler. You would never just drive over to your local muffler chain with her. No, this kind of purchase demanded at least one extensive meeting with a qualified professional.
When I walked in for my first new mufflers, my mechanic took a deep breath and put down his tools. He walked outside and circled the car. I followed. He lit a smoke and offered me one in a way that suggested I'd need it.
"Okay, first of all, she's got twin headers, so of course you're keeping two full exhaust lines all the way back to twin pipes in the rear." He looked at me closely. It was not a question.
"Of course, two full exhaust systems," I said. Anything less would be like giving a princess tea in a coffee cup.
My mechanic gave me a you're-doing-the-right-thing look and continued. "Now she's running cherry bomb mufflers. Loud ones, too. Are you happy with the sound?" I started to answer, but he wasn't done. "What are you after in terms of public perception? Both cruising, at idle, and flat out acceleration? What do you want the sound to make people feel?"
"Well, right now it's a little obnoxious." I said. "I'm thinking a lower, deeper sound, but still throaty at idle and noticeable in the low end. I want people to feel the torque from the sound, but not in an 'asshole in a muscle car' way. "
"Agreed," he said. "What about tone? Deeper bass kick or higher silky rumble?"
This went on for 45 minutes. And he wasn't even my regular mechanic.